What is the least common multiple of 20 and 36? Another way to say this is: $\lcm(20, 36) = {?}$
Solution: The least common multiple is the smallest number that is a multiple of 20 and 36. We know that 20 x 36 (or 720) is a common multiple, but is it the least common multiple? Write out the multiples of 36 until we find a number divisible by 20. 36, 72, 108, 144, 180, So, 180 is the least common multiple of 20 and 36.